CN202651806U - A battery energy storage power station smooth wind power generation control system - Google Patents

Abstract

The utility model proposes a smooth wind-power photovoltaic power generation control system of a battery energy storage station. The control system comprises a communication interface, a communication main machine, a data memory and a power control device, wherein the communication main machine respectively reads the real-time data of a wind power generation field, a photovoltaic power generation field and the battery storage station in operation by communication interfaces, and is respectively connected with the data memory and the power control device by a communication network. The power control device comprises a dynamic slope controller and a power distributor connected with the dynamic slope controller. The control system not only satisfies the application requirement of the energy storage system for suppressing wind-power photovoltaic power generation wave, but also effectively reduces the utilization rate of the energy storage system, so as to reduce the battery deterioration to the maximum limit and ensure long-term operation of the battery energy storage system.

Description

A battery energy storage power station smooth wind power generation control system

technical field

The utility model belongs to the technical field of smart grid and energy storage and conversion, and in particular relates to a control system for smooth wind and solar power generation of a battery energy storage power station.

Background technique

Due to the uncertainty and instability of wind power and photovoltaic power generation, the instantaneous rise or fall of wind power generation power will cause the output power to be unstable, making the grid-connected power of wind power and photovoltaic power generation fluctuate continuously. Moreover, as the proportion of wind power and photovoltaic power generation in the grid continues to increase, the smooth control of wind power and solar power output power has attracted more and more attention.

With the continuous development of batteries and their integration technologies, the application mode of large-scale distributed and centralized battery energy storage power stations will gradually become a preferred solution, and the application of battery energy storage systems to smooth the output fluctuations of wind power and solar power has gradually become a a feasible solution. By reasonably controlling the converter connected to the energy storage device, the energy storage system can be charged and discharged efficiently, which can largely solve the wind power and photovoltaic power generation due to the randomness, intermittency and volatility of wind power generation output. The problem of power instability is to meet the smooth output requirements of wind power and solar power generation, and effectively solve the power quality problems caused by the fluctuation of wind power and photovoltaic power generation to the grid frequency fluctuation. The wind-solar-storage combined power generation system is essentially a multi-energy system. How to coordinate the work of each power system is a key issue in the development of a multi-energy hybrid power generation system.

The battery energy storage power station can smoothly control the fluctuation of wind power generation power according to the smooth requirements of wind power and photovoltaic power generation output and the fluctuation rate limit requirements of grid-connected wind power generation. Therefore, it is necessary to carry out research on wind-solar-storage combined power generation system and propose related control methods. At present, there are very few patents, documents, and technical reports on smooth control of wind power generation output based on megawatt-scale high-power and large-capacity battery energy storage power stations, and in-depth research and exploration are needed.

At present, there are very few patents, documents, and technical reports on the monitoring and grid-connected operation of multi-type large-scale battery energy storage power stations, which require in-depth research and exploration.

Utility model content

In order to overcome the defects of the prior art, the purpose of the utility model is to provide a more efficient and stable battery energy storage power station smooth wind power generation control system.

The monitoring system of the battery energy storage power station of the utility model is realized through the following technical scheme:

A control system for smooth wind power generation of a battery energy storage power station, including a communication interface, a communication host, a data storage device and a power control device. the real-time data, the communication host is respectively connected with the data memory and the power control device through the communication network.

Further, the power control device includes a connected dynamic slope controller and a power divider, the dynamic slope controller generates a smooth target value of the total power of wind and solar power through the real-time data read by the communication host, and the power distribution Based on the smooth target value of the total power of wind and solar power generated by the dynamic slope controller, the controller determines the total power demand value of the battery energy storage power station and distributes it to the battery energy storage power station.

Compared with the prior art, the beneficial effects of the utility model are:

The control system of the utility model adopts a dynamic slope limiter, which satisfies the limit value of the change rate of the total power of wind and solar power generation. While meeting the requirements of the fluctuation rate limit of power generation, it can effectively reduce the burden caused by frequent use of batteries, minimize battery degradation, and ensure the healthy operation of batteries, so as to solve the problem of efficient control of energy storage power stations when smoothing wind and wind power generation fluctuations.

Description of drawings

Fig. 1 is a schematic diagram of the system access of the wind-solar-storage combined power generation equipment in the utility model;

Fig. 2 is an implementation block diagram of an embodiment of a smooth wind power generation control system based on a dynamic slope limiter of the present invention.

Detailed ways

The monitoring system of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Figure 1 shows the system connection topology of wind-solar-storage combined power generation equipment. As shown in Figure 1, the wind-solar-storage combined power generation system connected to the battery energy storage power station includes wind farms, photovoltaic power plants, battery energy storage power stations and power grids. Wind farms, photovoltaic farms and battery energy storage power stations are connected to the grid through transformers. The schematic diagrams of the internal connections of wind farms and photovoltaic farms are omitted here. The battery energy storage power station includes multiple lithium battery energy storage units connected in parallel, and each energy storage unit includes a bidirectional converter and multiple lithium ion battery packs, and the lithium battery energy storage unit can be activated through the bidirectional converter Stop control and charge and discharge power command, etc.

Fig. 2 is an implementation block diagram of an embodiment of a control system for smoothing wind and solar power generation of an energy storage power station based on a dynamic slope limiter of the present invention. As shown in Figure 2, the control system in this example includes: a communication interface, a communication host, a data storage device, and a power control device. The real-time data is sent to the data memory for storage. The power control device generates the smooth target value of wind and wind power generation and the total power demand value of the energy storage power station according to the real-time data, and stores them in the data memory: The total power demand value required by the energy station is sent to the battery energy storage station; on the other hand, the communication host outputs the smooth target value of the wind and solar power generation and the total power demand value of the energy storage station to an external monitoring device for monitoring.

The real-time data read by the communication host includes: the total power value of wind power generation, the total power value of photovoltaic power generation, the operating status value of each wind power generating set, the rated power value of each wind generating set, the operating state value of each photovoltaic generating The rated power value of the unit, the limit value of the fluctuation rate of wind and solar power generation, the maximum allowable discharge power value and the maximum allowable charging power value of the battery energy storage power station, etc.

The power control device includes a connected dynamic slope controller and a power divider, the dynamic slope controller is used to determine the smooth target value of the input wind and solar power total power, and the power divider is based on the dynamic slope controller generated The smooth target value of the total power of wind and solar power generation determines the total power demand value of the battery energy storage power station and distributes it to the battery energy storage power station.

The total power demand value of the battery energy storage power station for smooth wind and solar power generation is obtained by the following method:

为动态斜率控制器输出功率，作为风光发电平滑目标功率值；P_风光总为风光发电总功率值，作为动态斜率控制器输入功率，该风光发电总功率值等于通讯主机所读取的风力发电总功率值与光伏发电总功率值之和；P_储能总为电池储能电站总功率需求值。其中，求取

的具体方法为：In the above formula,

P _is the output power of the dynamic slope controller, which is used as the smooth target power value of the wind and wind power generation; The sum of the power value and the total power value of photovoltaic power generation; P _{energy storage} is the total power demand value of the battery energy storage power station. Among them, obtain

The specific method is:

A) Based on the operating state signals of each wind power generating set, the rated power value of each wind generating set, the operating state signal of each photovoltaic generating set and the rated power value of each photovoltaic generating set, the wind and wind power generation currently in grid-connected operation is calculated by the following formula (2): Total rated power of the unit:

为风机机组k的额定功率；u_风电k为风机机组k的运行状态，当该风机机组k运行可控时，此状态值为1，其他值为0；

为光伏机组k的额定功率；u_光伏k为光伏机组k的运行状态，当该光伏机组k运行可控时，此状态值为1，其他值为0；W为风机机组个数；V为光伏机组个数；上述各数据通过通讯主机直接读取。In the above formula,

is the rated power of the fan unit k; u _{wind power k} is the operating state of the fan unit k, when the fan unit k is in controllable operation, this status value is 1, and other values are 0;

is the rated power of the photovoltaic unit k; u _{photovoltaic k} is the operating state of the photovoltaic unit k, when the photovoltaic unit k is in controllable operation, this state value is 1, and other values are 0; W is the number of fan units; V is the photovoltaic The number of units; the above data are directly read through the communication host.

B) Based on the total rated power of the wind and solar generators currently running on the grid and the limit value of the fluctuation rate of wind and wind power generation, calculate the change speed of the limit signal required in the dynamic slope controller in real time, that is, the rise/fall change rate limit values are as follows: (3)-(4) calculation:

为动态斜率控制器输入功率的上升变化率限制值；

为动态斜率控制器输入功率的下降变化率限制值；

为风光发电波动率限制值；T_时间尺度为变化率的考察时间间隔。In the above formula,

The limit value of the rising change rate of the input power for the dynamic slope controller;

It is the limit value of the falling change rate of the input power of the dynamic slope controller;

is the limit value of the fluctuation rate of wind and solar power generation; the T _{time scale} is the inspection time interval of the change rate.

C) Setting the output power of the dynamic slope controller at the initial moment (t=1) as the first total power value of the wind and solar power that is sampled and input to the dynamic slope controller;

D) Calculate the change speed of the limit signal required in the dynamic slope controller in real time based on the total rated power of the wind and wind generator set and the limit value of the wind and wind power fluctuation rate in the current grid-connected operation;

In the above formula, P _{total wind power} (t) is the total power value of wind power generation (in kW) at the current sampling time t, and the total power value of wind power generation is equal to the sum of the total power value of wind power generation and the total power value of photovoltaic power generation at sampling time t, It can be read directly through the communication host; P _{wind total} (t-1) is the total power value of wind power generation (unit kW) at the previous sampling moment; Δt is the sampling period of the limited signal (that is, the total power value signal of wind power generation).

为止；对每一次的动态斜率控制器输出功率进行存储，作为基础数据供下一采样时刻基于变化速率限制条件进行判断时调用。所述基于变化速率限制条件进行判断的具体方法如下：E) Judging based on the rate of change limit condition until the output power of the dynamic slope controller at the current sampling time is obtained

So far; the output power of the dynamic slope controller is stored each time, and used as basic data for calling when judging based on the rate-of-change limiting condition at the next sampling time. The specific method for judging based on the rate-of-change limiting condition is as follows:

则

if

but

则

if

but

则

if

but

为当前采样时刻(即t采样时刻)经过变化速率限制后的输出功率(即t采样时刻动态斜率控制器的输出功率)；

为前一采样时刻经过变化速率限制后的输出功率(即t-1采样时刻动态斜率限制器模块的输出功率)。每两个相邻采样时刻之间为一个采样时间(即采样周期)Δt。In the formula,

is the output power of the current sampling time (i.e. t sampling time) after the rate of change limitation (i.e. the output power of the dynamic slope controller at t sampling time);

is the output power after the rate-of-change limitation at the previous sampling time (that is, the output power of the dynamic slope limiter module at the sampling time t-1). There is a sampling time (ie sampling period) Δt between every two adjacent sampling moments.

即F) Set the output power of the dynamic slope controller at the current sampling time (t sampling time) as the smooth target value of the total power of wind and solar power generation at the current sampling time (t sampling time)

Right now

The control system can not only meet the application requirements for the energy storage system to stabilize the fluctuation of wind and solar power generation, but also effectively reduce the utilization rate of the energy storage system, minimize battery degradation, and ensure the long-life operation of the battery energy storage system.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present utility model and not to limit them. The utility model has been described in detail in conjunction with the above embodiments, and those of ordinary skill in the art should understand that: those skilled in the art Personnel can still modify or equivalently replace the specific implementation of the present utility model, but these modifications or changes are all within the protection scope of the pending claims.

Claims (2)

1. A battery energy storage power station smooth wind power generation control system, characterized in that the control system includes a communication interface, a communication host, a data storage and a power control device, the communication host reads the wind farm, photovoltaic For the real-time data of the power plant and the battery energy storage power station during operation, the communication host is respectively connected to the data memory and the power control device through the communication network. 2. The system according to claim 1, wherein the power control device comprises a dynamic slope controller and a power splitter connected to each other, and the dynamic slope controller generates wind and landscape through the real-time data read by the communication host. A smooth target value of the total power generated, the power allocator determines the total power demand value of the battery energy storage power station based on the smooth target value of the total wind power generated by the dynamic slope controller, and distributes it to the battery energy storage power station .

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